Fig. 2. Structure, function, and main regulatory factors of AMPK.

AMPK is comprised of three subunits, namely α, β, and γ. It can be activated by CAMKK2, which is regulated by Ca2⁺ concentration, as well as by LKB1, consisting of STRAD, MO25, and LKB1. Additionally, AMPK can be activated by compounds, such as Salicylate and A-769662, or factors that increase AMP levels, including AMP analogues like AICAR, exercise, energy stress such as glucose deficiency, and drugs like aspirin or compounds such as metformin. The primary functions of AMPK are to promote the ATP synthesis process (FAO, glycolysis, glucose uptake, etc.), inhibit the ATP decomposition process (such as protein synthesis, lipid synthesis, gluconeogenesis, etc.), regulate mitochondrial homeostasis, and promote autophagy. AMPK AMP-activated protein kinaseST, PI3K phosphoinositide 3-kinase, CAMKK2 recombinant calcium/calmodulin-dependent protein kinase kinase 2, MO25 mouse protein-25, LKB1 Liver kinase B1, mTOR mammalian target of rapamycin, FBP fructose 1,6-bisphosphatase, ATM Ataxia Telangiectasia Mutated, BD binding domain, CBM carbohydrate-binding module, CBS Cystathionine Beta-Synthase, ATP adenosine 5’-triphosphate, ADP adenosine diphosphate, AMP adenosine monophosphate, CCCP Carbonyl cyanide 3-chlorophenylhydrazone, EMT Epithelial-mesenchymal transition, ATG9 autophagy-related protein 9, ULK1 Unc-51-like kinase, PGC1 peroxisome proliferator activating receptor C-coactivator 1, ERRs Estrogen-related receptors, PPARr peroxisome proliferators-activated receptors, MFF MAC-Forced Forwarding, DRP1 dynamin-related protein 1.